— 143 - 



that emulsin has both a synthetising and a hydrolysing action 1 ). To prove 

 this they diluted solutions of /?-ethylglucoside and glucose in ethyl alcohol 

 of different strengths with emulsin and after some lapse of time estimated 

 the proportion of glucose which was present in the solutions. It was then 

 shown that the synthetising action of emulsin increases with the concen- 

 tration of the alcohol. For example: with 95 p. c. alcohol 90 p. c. of the 

 glucose used had been converted into the glucoside after a lapse of 

 50 days. When 90 or 85 p. c. alcohol was used the reaction was accom- 

 plished sooner, but only 70 p. c. glucoside was formed. 



Chemical Notes. 



V. Grignard 2 ) has proposed a new nomenclature for poly cyclic hydro- 

 aromatic systems. In his opinion his nomenclature is more lucidly arranged 

 than that of von Baeyer. Grignard starts from a fundamental ring, which is 

 crossed by one or more bridges. The system is not called by the total 

 number of carbon atoms which it contains, but by the fundamental ring, 

 the form of which is at once perceptible. The bridges are regarded as 

 substitutes which are connected with the fundamental ring by their two 

 terminal points and of which the position and nature are determined by 

 the characteristic. In cases where only one bridge exists, the characte- 

 ristic follows the prefix "Bicyclo". The characteristic consists seriatim 

 of the figures of all the carbon-atoms which compose the bridge, including 

 its connecting points. By this means it is at once clear from which point 

 of the fundamental ring the bridge starts, where it ends, and what carbon 

 atoms it contains. If the bridge consists of more than two carbon atoms 

 the maximum value of the characteristics indicates at the same time the 

 total number of cyclic carbon atoms which are present. A double linking 

 in the bridge is indicated by the prefix "Bicycleno" in lieu of "Bicyclo". 

 Thus, for example, according to Grignard the systems I, II and III are 

 respectively called biq/dewo-(f ,7,5)-hexane, biq/cZ<mo-(l,7'8,4)-hexene-5 and 

 bic?/c7mo-(r,7,8,4)-hexene, while according to von Baeyer they are known 

 as: biq/do-(l,l,3)-heptene-l,7, bic2/cfo-(2,2,2)-octadiene-5,7 and blcyclo- 

 (2,'2,2)-octadiene-4-(l,7). Grignard's principles are also readily applicable 

 in those cases where the fundamental ring contains several bridges. The 

 ^number of rings as indicated in the prefix is determined by doubling the 

 number of the bridges. Pinene hydrate (IV) and borneol (V) would under 

 Grignard's system be described as trimethyl-l,7,7-bic^cZo-(2,7,4)-hexanol-l 

 and trimethyl-l,7,7-biq/do-(l,7,4)-hexanol-2, while in Baeyer's system 

 pinene hydrate is known as trimethyl-2,7,7,-biq/cZo-(l,l,3)-heptanol-2 

 and borneol as trimethyl-l,7,7-biq/cZo-(l,2,2)-heptanol-2. In the new 



*) Comp. Report April 1909, 17; October 1909, 19; October 1910, 18. 

 *) Bull. Soc. chim. IV. 11 (1912), 124. 



